This presentation introduces model concepts and terms, demonstrates some models, develops critical awareness of modelling issues, and enables use of published and accepted groundwater models. The regional scale, steady-flow, groundwater model demonstrates the principal behaviour of nitrate contamination from land use, while the stream function approach to contaminant transport addresses questions about response times of effects of land use change. The use of a steady-flow groundwater model for regional scale reduces computation time, which may be important for real-time stakeholder participation
